The field of electronic data processing has reached a high level of development. The development has lead to many services that are available in electronic data processing and that provide an abundance of functionalities. A service is a modular unit of a software application that is provided by a computer system, for example, a server or a personal computer (PC). A service may be accessible according to a specified standard and may be useable as a part of different applications. A plurality of services may be composed to give a composite service. A service may be easily accessible for example through the Internet or it may be accessible for example for employees of a company on an internal system for which the access is controlled.
An example for a service is a Web service that may be accessed through the Internet. In an example, data may be exchanged between one or more Web services in the XML standard according to internet based protocols. Composing Web services to give a composite Web service is a powerful way to create new applications that include a complete process. An example for such an application may be an online purchase of a specific product or service.
It is desirable that a composite service provides consistency, that is, the composite service terminates in a consistent state. The composite service may be able to provide the consistency depending on how the services of the composite service behave.
In a contribution to the WWW2005 conference in Chiba with the title “Ensuring Required Failure Atomicity of Composite Web Services” a transactional approach to composite Web services is addressed. The authors Sami Bhiri, Oliver Perrin, and Claude Godart propose transactional rules to verify that a composite Web service provides consistency.